1. Field of the Invention
The present invention generally relates to the field of semiconductors. More particularly, the invention relates to fabrication of capacitors in semiconductor wafers.
2. Background Art
Decoupling capacitors are commonly utilized to reduce electrical noise, such as switching noise, in electronic circuits. For example, decoupling capacitors can be utilized to reduce electrical noise, such as switching noise in electronic circuits integrated in semiconductor dies, such as large scale integrated (LSI) circuits. However, decoupling capacitors can compete with other circuit elements, such as semiconductor devices, for limited space on a semiconductor die.
Conventionally, Metal-Insulator-Metal (MIM) capacitors and Metal Oxide Semiconductor (MOS) capacitors have been utilized for decoupling capacitors in electronic circuits fabricated on semiconductor dies. However, decoupling MIM capacitors and MOS capacitors can consume a large amount of die space. Thus, by utilizing MIM capacitors and/or MOS capacitors as decoupling capacitors, the amount of die space available for other circuit elements, such as semiconductor devices, can be undesirably and significantly reduced.